import java.sql.*;

public class DBTest {
    public static void main(String[] args) {
        // 1. 数据库连接信息 (URL, 用户名, 密码)
        String url = "jdbc:mysql://localhost:3306/library_management?useSSL=false&serverTimezone=Asia/Shanghai&allowPublicKeyRetrieval=true";
        String username = "root"; // 你的数据库用户名
        String password = "07162007lyr"; // 你的数据库密码

        String name = "admin";
        String pass = "admin123";

        Connection conn = null;
        PreparedStatement prep = null;
        ResultSet rs  = null;

        int id = 0;
        String email=null;

        String sql ="select * from user where username = ? and password = ?";

        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            conn=DriverManager.getConnection(url,username,password);

             prep= conn.prepareStatement(sql);

            prep.setString(1, name);
            prep.setString(2, pass);

            rs = prep.executeQuery();
            while  (rs.next()) {
                id = rs.getInt(1);
                email = rs.getString(6);
            }

        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            try {
                rs.close();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            try {
                prep.close();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            try {
                conn.close();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
        }

        System.out.println(id);
        System.out.println(email);
    }
}
